Posted on 02/07/2012 11:05:54 AM PST by DeoVindiceSicSemperTyrannis
That is always the case, noticeable at significant distances.
The speed of light is always going to be far greater than the speed of sound, at any elevation.
not only will he slow down, he will heat up.
Altitude *IS* a factor. The higher up you go in the column of air, the lower the weight of the atmosphere above it.
When you are over a mile up, it is noticeable at much less than significant distances.
He is free falling, not rocket propelled. He is not going to experience more than 1 G. Gravity and friction are the only forces involved.
During de-acceleration he may have greater force through his harness, but before.
It has been done before, so it is survivable.
That sounds about right.
If you want to see what it is like to drop from 94,000+ feet watch this video.
http://www.youtube.com/watch?v=Pl2OIQMbZhg
I think what would be a fun project to do is make an R/C skydiving dummy that you would drop from a balloon. Once it gets into range pop the chute and guide it back for a landing.
What an idiot.
I hope he enjoys breaking the sound barrier before deploying his chute. It will probably be the last thing he ever experiences except for frictional heating.
“Cap Troopers Rule!” - Johnny Rico
Note: 120MPH is based on a lot of assumptions as well - not the least of which being a large, stable ‘box man’ position. It is also just a rough estimate.
At a given weight, larger jumpers will be slower than smaller jumpers. A tight ‘mantis’ position will be faster than an open ‘box man’ position. Head down will be significantly faster than flat.
I’ve personally achieved speeds of approximately 160MPH in freefall while flat, though my average fall rate has been closer to about 135MPH...
Terminal velocity is when the forces of gravity on an object reach a homeostatic point with the resistance of the medium that is being traversed. By going to an altitude of 120,000+ feet, he’s hoping to accelerate as much as he can in a virtually frictionless environment where the forces to counter the acceleration from gravity are mitigated.
I heard his interview. The air was so sparse up there that when he stepped clear of the gondola he felt like he was just floating. He had to look back at the balloon receding to verify he was actually falling.
Show me how the physics don't support it. I did the math, and the physics seem to support it on this end. Given that terminal velocity of an object increases by 1% for approx every 160m of altitude he's on more than safe ground.
He's giving himself almost 12,000m more elevation than the previous record holder used to set the record. That's not only a substantial increase in time to accelerate, but it will occur in an atmosphere with markedly less friction to boot. He should be close to the old record by the time he reaches the altitude that attempt started at. He's still going to have a good 10,000m after that before resistance becomes the greater force and he begins to scrub speed.
Which bring up another concern: Parachute aside, he's going to start slowing down a lot once he enters the troposphere, and that energy has to go somewhere, and it will. He's going to heat up. All that kinetic energy is going to be converted into heat.
Already been done, an american test pilot or some such did this a long time ago.. but nice to see someone else deciding to try it.. I wouldn’t mind doing the whole ride to the edge of space, would be hell of a lot cheaper than a rocket ship.
Yeah, but how aren't temperature and density related to altitude? For all practical purposes, the two are one and the same. The higher you go, the colder and less dense the atmosphere. Even the thermosphere isn't really an exception. You might find molecules and atoms exited to temperatures that would melt concrete, but the molecules are so far apart (kilometers) that you'd flash freeze if you stepped out into it. Even if you came into contact with any of the superheated gasses, the total amount of energy would be so slight, that you couldn't physically detect it without advanced instruments.
I should have been more clear. That's what I meant when I said the physics don't support it. IF he gets the rest of it correct and approaches the SOS...he won't survive and he'll start burning up before he hits that mark....thus seriously messing with his aerodynamics and keeping him short of the mark.
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